A known printer is capable of printing an image by using a cyan ink C, a magenta ink M, a yellow ink Y, a black ink K, a light black ink Lk, a light light black ink LLk, a red ink R, and a blue ink B. The printer generates a new lookup table (LUT) from two types of LUTs. One LUT maps RGB color values to respective CMYKLkLLk color values. The other LUT maps the RGB color values to respective CMYKRB color values. The printer synthesizes these two LUTs at a composite ratio α to generate the new LUT. The generated new LUT maps the RGB color values to respective CMYKLkLLkRB color values. The composite ratio α is determined on the basis of a distance between a gray line in an RGB color space and a grid point whose data is a target of the synchronization.
The printer also generates a LUT capable of reducing the consumption of an ink with the small remaining amount. To generate this LUT, the printer synthesizes a normal LUT prioritizing the image quality and another LUT having a small output value for a color of the ink with the small remaining amount. In this case, the remaining amount of this ink is used as a parameter to determine the composite ratio α.